Researchers say the findings could help them personalize treatment for certain children with cancer to prevent the toxic effects of anthracycline chemotherapy upon the heart.

"Although we depend heavily on anthracyclines for treating children with cancer, we are fully aware of their toxic effects to the heart. We also know that some patients -- despite being exposed to higher doses -- don't develop heart problems, while others with little exposure have considerable cardiac damage," said study senior author Dr. Smita Bhatia, professor and chair of the department of population sciences at the City of Hope National Medical Center in Duarte, Calif., in a news release.

"Our results are a good example of how understanding a cancer patient's genetic makeup can help us better tailor individual therapies," Bhatia said.

About eight out of every 10 children with cancer survive, but they may suffer from health problems related to treatment later in life.

The researchers studied 165 childhood cancer survivors who were diagnosed with heart disease between 1996 and 2008, and compared them to a control group of 323 cancer survivors without heart disease. Among the children who had been treated with low doses of anthracyclines, particular genetic variants of the CBR gene boosted the risk of heart disease.

In the future, oncologists may be able to screen for these gene variants and if necessary, to choose a therapy that will not damage the heart.

The study is scheduled to be released June 7 at the American Society of Clinical Oncology annual meeting in Chicago.